[CH3:1][Mg]Br.[Cl:4][C:5]1[CH:10]=[CH:9][C:8]([C:11]([CH:13]2[CH2:15][C:14]2([F:17])[F:16])=[O:12])=[CH:7][CH:6]=1>C(OCC)C>[Cl:4][C:5]1[CH:6]=[CH:7][C:8]([C:11]([CH:13]2[CH2:15][C:14]2([F:16])[F:17])([OH:12])[CH3:1])=[CH:9][CH:10]=15.7 ml (17.1 mmol) of a 3N solution of methylmagnesium bromide in diethyl ether were added to 2.47 g (11.4 mmol) of the compound from Example 124A in 40 ml of diethyl ether at RT, and the mixture was stirred at RT overnight. The reaction mixture was added to a saturated, ice-cold aqueous ammonium chloride solution, the phases were separated, the aqueous phase was extracted with dichloromethane, and the combined organic phases were dried over magnesium sulfate, filtered and concentrated. The residue was purified by flash chromatography on silica gel (mobile phase: toluene/ethyl acetate gradient) to result in 2.09 g (78% of theory) of a mixture of the diastereomers of the title compound.
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